1. Field of the Invention
The present invention is for a clamping system and, more particularly, is for a system including a variable geometry clamp joining telescoping box tubes, such as for gate arms.
2. Description of the Prior Art
Prior art clamping systems for gate arms were bolted together. The amount of time for assembly in the field was sometimes significant, because it was necessary to drill holes. In later years, the clamping systems came with predrilled holes, but sometimes the predrilled holes did not always align or were not drilled for the proper distances.
The present invention overcomes the problems with the prior art assembly of clamping systems for gate arms by providing a box tube clamping system. SUMMARY OF THE INVENTION
The general purpose of the present invention is to provide a box tube clamping system including telescoping box tubes and an interceding variable geometry clamp. Such joined box tubes can be used for railroad grade crossing arms, parking lot security arms, or other situations requiring the attachment of box tubes or arms along a longitudinal axis. An outer box tube telescopingly accommodates an inner box tube of slightly lesser dimension. The outer box tube and the inner box tube are dimensioned such that substantially planar portions of a variable geometry clamp can be accommodated between the lower planar panels of each of the box tubes. The lower panel of the larger of the box tubes includes an elongated hole through which vertically oriented posts of the variable geometry clamp protrude. The variable geometry clamp is comprised of a center wedge assembly flanked by a left wedge assembly and a right wedge assembly. Each wedge assembly includes a wedge plate having opposing bevels and a holed post extending downwardly from the bottom surface thereof. An upwardly facing bevel of the left wedge plate and an upwardly facing bevel of the right wedge plate align intimately in edge to edge, bevel to bevel, horizontal fashion to oppositely oriented downwardly facing bevels of the center wedge plate. A bolt extending through the holes in the downwardly extending posts is incorporated to draw the left and right beveled wedge plates of the left and right wedge assemblies together against the center wedge plate of the center wedge assembly to alter the geometry of the clamp by causing forced upward deflection of the center wedge assembly by action of the impinging bevels. Such a change to the vertical extent of the variable geometry clamp forces mutual frictional and secure engagement of the inner box tube and the outer box tube.
According to one embodiment of the present invention, there is provided a box tube clamping system for secure joining of telescoping outer nad inner box tubes.
An alternate embodiment discloses installation spacers in the variable geometry clamp which aid in insertion of the inner box tube into the outer box tube.
One significant aspect and feature of the present invention is a box tube clamping system having a variable geometry clamp disposed between like planar panels of telescoping box tubes.
Another significant aspect and feature of the present invention is a variable geometry clamp having a center wedge assembly disposed between adjoining wedge assemblies.
Still another significant aspect and feature of the present invention is the use of wedge assemblies having beveled wedge plates and holed posts extending downward therefrom.
Yet another significant aspect and feature of the present invention is the intimate horizontal alignment of beveled surfaces of the beveled wedge plates.
A further significant aspect and feature of the present invention is the forcing together of adjoining wedge assemblies of the variable geometry clamp to vary the vertical extents of the variable geometry clamp to force mutual frictional engagement of the inner box tube with the outer box tube.
Still another significant aspect and feature of the present invention is the use of installation spacers with a variable clamp assembly which maintains a low and orderly variable clamp assembly profile to aid in the installation of the inner box tube within the outer box tube.
Having thus described embodiments of the present invention and mentioned several significant aspects and features thereof, it is the principal object of the present invention to provide a box tube clamping system.